1 Division of Pulmonary and Critical Care Medicine, Johns Hopkins University, Baltimore, Maryland.
2 National Heart and Lung Institute, Imperial College London, London, United Kingdom.
3 Division of Pulmonary, Critical Care, and Sleep Medicine, University of Washington, Seattle, Washington; and.
4 Center of Innovation for Veteran-centered and Value-driven Care, Veterans Affairs Puget Sound Health Services Research & Development, Seattle, Washington.